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.\" Common Development and Distribution License ("CDDL"), version 1.0.
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.\" 1.0 of the CDDL.
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.\" Copyright 2017 Nexenta Systems, Inc.
.\"
.Dd March 28, 2017
.Dt MBSTOWCS 3C
.Os
.Sh NAME
.Nm mbstowcs ,
.Nm mbstowcs_l
.Nd convert a multibyte character string to a wide-character string
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Ft size_t
.Fo mbstowcs
.Fa "wchar_t *restrict pwcs"
.Fa "const char *restrict s"
.Fa "size_t n"
.Fc
.In stdlib.h
.In xlocale.h
.Ft size_t
.Fo mbstowcs_l
.Fa "wchar_t *restrict pwcs"
.Fa "const char *restrict s"
.Fa "size_t n"
.Fa "locale_t loc"
.Fc
.Sh DESCRIPTION
The
.Fn mbstowcs
function converts a multibyte character string
.Fa s
beginning in the initial conversion state into a wide-character string.
If
.Fa pwcs
is not
.Dv NULL ,
the converted characters are stored into array pointed to by
.Fa pwcs .
.Pp
Conversion continues up to and including a terminating null character, which is
also stored, or until
.Fa n
wide-characters have been stored into the array pointed to by
.Fa pwcs .
.Pp
The behavior of
.Fn mbstowcs
function is affected by the
.Ev LC_CTYPE
category of the current locale.
.Pp
The
.Fn mbstowcs_l
function behaves identically to
.Fn mbstowcs ,
except instead of using the current locale, it uses the locale as specified by
.Fa loc .
.Sh RETURN VALUES
The
.Fn mbstowcs
and
.Fn mbstowcs_l
functions return the number of wide-characters successfully converted, not
including the terminating null
.Pq if any ,
or
.Li \-1
if conversion encounters a sequence of bytes that does not form a valid
character.
.Sh ERRORS
The
.Fn mbstowcs
and
.Fn mbstowcs_l
functions will fail if:
.Bl -tag -width Er
.It Er EILSEQ
An invalid multibyte sequence was detected.
.It Er EINVAL
The conversion state is invalid.
.El
.Sh INTERFACE STABILITY
The
.Fn mbstowcs
function is
.Sy Standard .
The
.Fn mbstowcs_l
function is
.Sy Uncommitted .
.Sh MT-LEVEL
.Sy MT-Safe
.Sh SEE ALSO
.Xr mbsnrtowcs 3C ,
.Xr mbtowc 3C ,
.Xr newlocale 3C ,
.Xr setlocale 3C ,
.Xr uselocale 3C ,
.Xr wcstombs 3C ,
.Xr attributes 7 ,
.Xr environ 7 ,
.Xr standards 7
